Internal-combustion engine



- H. JUNKERS.

INTERNAL COMBUSTION ENGINE. APPLICATION FILED MAY 9.1913. RENEWED AUG.3.1919,.

Patented Oct. 28,1919.

2 S HEETSSHEET 1.

- Inventor.

H.JUN K ERS.= INTERNAL COMBUS Tl0N ENGINE. I APPLICAT|ON F|| .ED MAY9,1911% RtNEWED AUG-13.1919.

Patented 0ct.28,-l9 l9.

2 SHEETSSHEET 2.

Inventor.

Witnesses.

UNITED STATES PATENT OFFICE.

HUGO JUNKERS, OF AACHEN, GERMANY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO L.M. WHEELOCK, 0F BOSTON, MASSACHUSETTS.

INTERNAL-COMBUSTION ENGINE.

To all whom it may concro'n:

Be it known that I, HUoo Jnxnnus, a citizen of the German Empire,residing at Aachen, No. (38 BlSllltll.ClSt-1'., Kingdom of Prussia,Empire of (Jrermany, have invented certain new and useful Improvementsin Internal-Combustion Engines; and I do here by declare the followingto be a full, clear, and exact description of the invention, suclr aswill enable others, skilled in the art towhich it appertains to make anduse the same.

This invention relates to two-cycle internal combustion engines and itsobject is to provide improved means for increasing the power develo )edby such an engine and 'for facilitating t e control of the operation ofthe engine.

The present invention constitutes an improvement upon that disclosed inPatent No. 891,078, granted to me June 16, 1908. That patent disclosesmeans for controlling the power developed by an internal combustionengine by a throttling device operated by hand or by the governor of theengine for controlling the. pressure within a suitable receiverconnected to the exhaust outlet of the engine. In this way, the quantityof air for combustion or the charge present in the cylinder at thecommencement of the compression stroke may be regulated if desired.

The object of the present invention is to provide' an improvedconstruction of this character whereby objectionable changing ofthe backpressure of the exhaust as the conditions of operation of the enginechange are eliminated. This is accomplished by the provision of meansfor maintaining a substantially constant pressure of the exhaustthroughout the changing conditions of operation of the engine; in otherwords, the charge of air in the cylinder prior to the compression strokeis always at a pressure higher than atmospheric pressure. The inventionalso involves the provision of means whereby thissubstantially constantpressure of the exhaust may be regulated as desired to increase ordiminish the power developed by the engine, such regulation beingeffected either manually or auton'iatically.

My improved construction is particularly Specification of LettersPatent.

Renewed August 13, 1919. Serial No. 317,377.

advantageous when used in connection with engines which must start upwith a large torque, such for instance as locomotives, hauling enginesand the like. In the operation of such engines. it would be practicallyimpossible to maintain the requisite pressure in the exhaust by manualmanipulation of a throttling valve in accordance with the varying speedand fluctuating torque; furthermore, the operator would be fullyoccupied at the time of starting such an engine with the mechanismcontrolling the admission of fuel to the engine.

"An engine constructed in accordance with the invention would preferablybe arranged so that when atmospheric pressure prevails in the exhaustchamber, that is, when the engine is not in operation, the opening forthe exit of the exhaust from the chamber would be completely closed. Asa result, on starting the engine with compressed air, the requiredpressure in the exhaust chamber would be quickly attained. For thispurpose the starting air alone would suflice. This would afford a highinitial charging pressure for the first-charges of fuel to be ignited.

The invention may also be employed to advantage in engines which aresubjected to a temporary or continuous overload. Its use obviates thenecessity of constant manual adjustment of the throttling device withchanges in the torque and speed. It is useful also in engines operatingcontinuously under a constant overload and at a fixed speed. In suchengines a stationary nonautomatic throttling device controlling theexhaust from the engine would become fouled by accunmlating grit and thelike, with the result that the area for the exit of the exhaust wouldbecomerestricted and cause a change in the exhaust pressure.

The invention will be better understood by reference to the followingdescription taken in connection with the accompanying drawings, in whichFigure 1 is a sectional view showing a spring-controlled throttlingvalve in the out let conduit.

Fig. 1* is a similar View showing the throttling valve moved by a pistonactuated by a fluid Whose flow is controlled by the governor.

Patei1ted'0ct.28, 1919.

Fig. 2 is a sectional view of a construction employing a welght-loadedthrottling device in one outlet passage and a positive hand-actuatedthrottling device in another outlet passage.

Fig. 3 is a sectional view-of a construction. in which a spring-actuatedthrottllngde=.

vice in the outlet conduit is subject to both automatic and'manualactuation.

Fig. i: is a sectional view of a construction employing aspring-actuated valve in which the tension of the spring may beadjusted.

Fig. 5 is a sectional view of a construction in which the position ofthe throttling device is regulated mechanically under the control of apiston which is subjected to the pressure in the exhaust chamber.

Fig. 6 shows a construction similar to that ber 1 through the opening 2and out by the exhaust pipe 3. The throttling valve is shown at l and itis held yieldingly upon its seat by a spring 5. Fig. 1 shows a construction similar .to that shown in Fig. 1 except that the valve spindle6 of the throttling valve 1 has a piston 7 on its end which piston moveswithin a cylinder 8. The space behind. the piston 7 receives compressedair from a pipe 9, the air being supplied from the air-receiver of theengine or from a. separate source. The compressed air admission valve 10is connected to the governor 11 through the connecting rods 12.

With the apparatus constructed as shown in Fig. 1 or Fig. 1 the pressureof the air with which the cylinder is charged and the back pressurewithin the receiver 1 are maintained at a predetermined point, thissubstantially constant pressure being determined upon by reference tothe amount of increase inthe output of the engine desired. The quantityof fuel admitted to the engine, would, of course, be varied inaccordance with the power to be developed. The ope *ation of the enginewould be similar to the normal operation except that it takes place at ahigher pressure level. This method of operation involves substantiallyconstant back pressure of the exhaust and variation of the fuelsupplied, the speed and the torque. The back pressure of the exhaust ismaintained substantially constant by the valve member controlling theexit from the exhaust receiver, which valve member is held yieldinglyupon its seat under a definite load. This definite load assume may beprovided by spring as in Fig. 1

pressure as in Fig. 1.

In Fig. 2 a construction is shown wherein anautomatic throttling deviceis employed and, in addition thereto, a throttling device "which isactuated by hand or by the governor of the engine. The exhaust chamberis shown at 13- having a port 14 therein Two conduits l5 and 16 leadfrom this chamber 13, the conduit 15 being for the exhaust which passesthrough the port 14:. The manually actuated throttling element consistsof a butterfly valve 18 operated by .a lever 17. The automaticthrottling is effected by a valve 19 controlling the port 14 and havinga spindle 20 which is adapted to carry a plurality of weights 21. Theseweights form the'load upon the valve controlling the outlet from theexhaust chamber instead of the spring shown for that purpose in Fig. 1.Compared with the preceding constructions, however, the construc tionshown in Fig. 2 possesses a disadvantage in the inertia of the mass ofthe weights; therefore, for high-speed engines the method of loading bymeans of weights is recommended to a less degree. Any of the forms ofautomatic controlling valves for regulating the pressure of the exhaustas herein shown may be provided with a positively-operated valve in themanner indicated in Fig. 2 if desired, such positively operated valvebeing actuated either by hand or by the engine.

The automatic and positively operated valves may be combined in a singlestructure if desired. But in such a construction they should be capableof independent operation so that total closing' may be effected only bythe automatic valve. in order to guard against an excessively highpressure in the exhaust receiver. Such a construction is shown in Fig.3. In this. figure, the exhaust gases from the chamber 22 pass throughthe opening 23 into the exhaust pipe 24. The throttling valve is shownat 25 and it is held yieldingly upon its seat by a spring 26. Abell-crank lever 27 has one end thereof entering an eye 30 in the stemof the valve so that by rocking this bell-crank lever on its pivot bymeans of a suitable connection thereto, the valve 25 i may be positivelyraised from its seat. The end of the bell-crank lever has an amountofplay in the eye 30 of the valve, which a port controlling an outletthrough pipe with the eye 30 and the manual operation of the valve thusprevented. Also, the dethe eye 30 coact with the frame of the valve to.form a stop.

F 1g. 4 shows a loaded throttling device,

the loading of which is made to vary in accordance with theturning-moment or torque of the engine. The exhaust chamber 31 has andthis port is controlled by a valve 3 which is held yieldingly upon itsseat by a spring'34. The spring 34 is initially compressed to therequired extent by adjustment of the cap 35 for the spring. This adjustment is effected by means of the spindle 36 of the therefore, openedmore and more.

cap 35 which spindle is splined to the frame in which it is mounted. Thespindle is shifted lengthwise-by a wheel 37 mounted in the frame andhaving a threaded opening which receives the threaded portion of thespindle 36. The wheel 37 is actuated by a wheel 39 on a shaft 38 and thelatter is turned in accordance with the speed or the load on theengine'so as to vary the tension of the spring 34. The required rotationof shaft 38 may be provided for in any suitable manner. Thus. the shaftmay be made 'to turn in accordance with changes in the quantity of fuelsupplied in the engine, or the position of the fuel supply lever, or thequantity of scavenging air. By operating in this way, varying the loadon the valve controlling the exhaust with changes in the supply of fuelto the engine, a saving in power consumed in the pumps is effected.

In the construction shown in Fig. 5, the gases pass out of'th exhaustchamber 40 through the port 41 and the pipe 42. A piston is shown at 43subjected to the pressure existing within the exhaust chamber 40. Theiston 43 is positioned by a spring 44 of deiiiiite tension. If thepressure in the receiver is greater than the load on the valve, thepiston moves outward and by means of the lever 45 the sleeve 46is'moved, and pressed against the friction-disk 47. This dish 47, aswell as the opposite disk 48, is driven by the gear 49 from any suitablesource of power. The'sleeve 46 is thus rotated and also the shaft 50 onwhich sleeve 46 is splind. The rotation of shaft 50 affects axialmovement of a nut 51 threaded on shaft 50 and connected by a bell-cranklever 5:2 to the throttling device 53 whic is,

his movement of valve 53 is continued until the pressure in the receiver40 becomes equal to the spring load 44 on piston 43. When this point isreached, the sleeve 46 disengages disk 47 and th opening movement ofvalve 53 terminates. On the other hand, if the pressure in the receiver40 drops below the spring load 44, the sleeve 46 engages with thepositively rotating friction-disk 48, with may the result that the valveis moved toward the closed position. \Vhen the piston is loaded by aspring as shown in Fig. 5, the

spring must be so set. that its tension is balanced by the desiredpressure in the re ceiver 40 when the. sleeve 46 is in the neutralposition. Y

Fig. (5 shows a construction in which the features shown in Figs. 4 and5 are combined. Thetension of the spring 55 loading the piston 54 can bealtered by changing the position of the cap 56 by means of the liollowspindle 57. This spindle is exteriorly threaded, is splined in the framein which it is mounted and has a wheel 58 threaded thereon. This wheelis rotated by the shaft 5!) in accordance with the power developed bythe engine. This construction is similar to that of .the adjustablethrottling device shown in Fig. 4. The stem of the piston 54 passesthrough the hollow shaft57 and is connected to a lever 60. Thesleevemoved by this lever 60 and -all of th parts associated therewith-aresimilar to the corresponding parts shown in Fig. 5, so that an exhaustback pressure depending .upon the load or torque is obtained.

I wish it understood that the utility of the invention is not confinedto any special type,- of two-cycle internal combustion engines, butthat, on the contrary, it is applicable to various types of two-cyclegas en gines and oil engines whether operated by the explosion of thegaseous mixture or by more or less slow combustion of the mixture.

l urthermore, the constructions herein illusnected to the exhaust outletfrom the cylinder and yielding means for maintaining a predeterminedpressure above atmospheric pressure within the receiver with all loadson the engine and at all speeds of revolution of the engine shaft;substantially as described.

2. A two-cycle internal combustion engine having means for increasingthe power developed by the engine by automatically con-trolling theexhaust from the cylinder of the engine comprising a receiver con-.nected to the exhaust outlet from the cylinder, yielding means formaintaining a predetermined pressure above atmospheric pressure withinthe receiver with all loads on the engine and at all speeds ofrevoludetermined pressure above atmospheric pres'.

sure Within the 'receivelrwith all loads on V the engine and at allspeeds of revolution of the engine shaft, and means for automaticallyvarying said predetermined pressure in accordance with the powerdeveloped by the engine; substantially as described.

at. A tworcycle internal combustion engine having means for increasing.the' power developed by the engine comprising devices for automaticallycontrolling the exhaust pressure in the cylinder with all loads and atall speeds of revolution consisting of means interposed in thepath ofthe exhaust from the cylinder for-maintaining a predetermined pressureabove atmospheric pres sure, said means being subjected to a load tohold it yieldingly in a definite position;

substantially as described.

5. A two-cycle internal combustion engine having "devices forautomaticallycontrolling the exhaust pressure in the cylin der withallloads and at all speeds of revolution comprising means interposedinthe' path of the exhaust from the cylinder for ieaaosa maintainingafpredetermined pressure above atmospheric pressure, said means beingsubjected to a load to hold it yieldingly in a definite position, andmeans for automatically varying said load under the engine;substantially as described.

6. A two-cycle internal combustion enine having meansfor controlling theexliaust from the cylinder thereof comprising a. receiver connected tothe exhaust outlet.

v 4 7 the control of o fromthe cylinder, a valve controlling an outletfrom said' receiver, means for subjecting the valve to pressure to holdit yieldingly in a predetermined position and means for varying thepressure to which the valve is subjected in accordance With the powerdeveloped by the engine; substantiallyas described.

T. An internal combustion engine having means for controlling theexhaust from the cylinder thereof, comprising a receiver connected tothe exhaustoutlet. from the cylinder, a valve controllingan' outlet fromthe receiver, means for positioning the ,valve, a yielding membercommunicating with the receiver and responsive, to the pressure eX-isting-therein ELDCl DIBClIiLHlS IH controlled by the position ofsaidyield'ing member for actuating the valve positioning meanssubstantially as described,

In testimony whereof I affix my signature,

Witnesses.

' HUGO} JUNKERS,

in presence of two Witnesses:

vEMIL VVERGIEN,

HERMANN FISCHER.

